EP 1876152 A3 20081001 - Process for physico-chemical adaptation of chemical gypsum or phosphogypsum for use in cement formulations and other construction materials
Title (en)
Process for physico-chemical adaptation of chemical gypsum or phosphogypsum for use in cement formulations and other construction materials
Title (de)
Verfahren zur physikalisch-chemischen Anpassung von Chemiegips oder Phosphorgips zur Verwendung in Zementrezepturen und anderen Baumaterialien
Title (fr)
Processus d'adaptation physico-chimique d'un gypse chimique ou phosphoplâtre pour utiliser dans des formules de ciment et avec d'autres matériaux de construction
Publication
Application
Priority
VE 150706 A 20060703
Abstract (en)
[origin: EP1876152A2] The present invention relates to the application of a novel process for the chemical and physical adaptation of chemical gypsum or phosphogypsum coming from the production of phosphoric acid and its use as a setting retarding agent in Portland type cements or in the preparation of other materials for construction. The adaptation is based on reactions in the solid state or in the presence of small amounts of water between the phosphogypsum and the agglutinating-neutralising agents, primarily by the application of oxy- and hydroxy-compounds, without rejecting the respective carbonates, of magnesium, aluminium and mainly calcium carbonate, along with mixtures thereof and later preparation of self-hardening pellets which facilitate its transport and handling. The technological process associated with the invention notably simplifies the number and type of unitary operations, and the preparation of pellets of mixtures of phosphogypsum, along with a reduction in energy costs due to operating at low temperatures (150 °C) for short times (1-2 hours) and a reduction in the quantities of neutralising agents, and it also minimise the volume of water required in the process.
IPC 8 full level
C04B 7/42 (2006.01); C04B 11/00 (2006.01); C04B 11/26 (2006.01)
CPC (source: EP US)
C01F 11/46 (2013.01 - EP US); C04B 7/424 (2013.01 - EP US); C04B 11/005 (2013.01 - EP US); C04B 11/26 (2013.01 - EP US); C04B 18/02 (2013.01 - EP US); C04B 22/144 (2013.01 - EP US); C04B 28/143 (2013.01 - EP US); C22B 1/2406 (2013.01 - EP US); C01P 2004/50 (2013.01 - EP US); C04B 2103/22 (2013.01 - EP US)
Citation (search report)
- [X] DE 2160205 A1 19730607 - KNAUF WESTDEUTSCHE GIPS
- [A] DE 2908266 B1 19800724 - KNAUF WESTDEUTSCHE GIPS
- [A] US 4193812 A 19800318 - CASPAR JEAN-PIERRE [FR], et al
- [A] GB 1187664 A 19700415 - MODULAR PLASTICS DEVELOPMENTS [GB], et al
- [A] GB 1468318 A 19770323 - CHARBONNAGES STE CHIMIQUE
- [A] AU 1431670 A 19711028
- [T] ULMMANNS ENCYCLOPEDIA OF INDUSTRIAL CHEMISTRY: WIRSCHING, FRANZ: "Calcium Sulfate", 2005, WILEY-VCH VERLAG GMBH, WEINHEIM, XP002490516
Designated contracting state (EPC)
AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC MT NL PL PT RO SE SI SK TR
Designated extension state (EPC)
AL BA HR MK RS
DOCDB simple family (publication)
EP 1876152 A2 20080109; EP 1876152 A3 20081001; US 2008003174 A1 20080103; US 7585485 B2 20090908
DOCDB simple family (application)
EP 07008619 A 20070427; US 78622007 A 20070411